What was daily life like for Native Americans at Mission San Gabriel Arcángel? What did they eat? What jobs did they do? An introduction to life at Alta California’s 4th Spanish Mission. Who Founded Mission San Gabriel? Mission San Gabriel Arcángel was the 4th mission established in Alta California. The mission was founded on September 8, 1771 by Fr. Junípero Serra along with Fr. Pedro Benito Cambón and Fr. Ángel Somera. Frs. Cambón and Somera became it’s first resident priests. Where is Mission San Gabriel Located? Mission San Gabriel Arcángel is located about 20 minutes from downtown Los Angeles and was established near the San Gabriel River, where the Tongva…